Many high performance computing systems have electronic components that generate a great deal of heat during operation. These systems often have a maximum operating temperature. If the temperature of the components of the computing system exceeds the maximum operating temperature, they do not operate reliably.
Therefore, many such systems are cooled using a ventilation system. Some ventilation systems simply allow air to pass over the warm components, so that the heat dissipates in the air. Other ventilation systems are forced air systems in which a fan is used to actively move air across (or past) the electronic components that are to be cooled. The air absorbs heat generated by those components and transfers it, under the influence of the fan, away from the components, to cool them. Other cooling systems are used as well, such as liquid cooling systems.
Many high performance computer systems also have a minimum operating temperature. If the temperature of the components of the computing system drops below the minimum operating temperature, they do not operate reliably either. Therefore, if the inlet air used to cool the computing system is below the minimum temperature, then the computing system may not operate reliably.
Some computing systems use free air cooling in which the cooling air is drawn from outside the enclosure, building or facility where the computer system is deployed. Depending on the geographic region where the computer system is deployed, this inlet air may be well below the minimum air temperature for reliable operation. Therefore, some current systems heat the inlet air before it is introduced into the computer system.
One current system for preheating the inlet air uses exhaust air from the computing system. The exhaust air is re-circulated back to the inlet section and mixed with the fresh, ambient air drawn into the inlet section for cooling. This is done in an attempt to have the warmer exhaust air mix with the cooler ambient air, in order to preheat the ambient air before it is used for cooling the computer system.
However, this has a number of significant disadvantages. Using this type of pre-heating, it can be difficult to maintain an even temperature distribution across the air inlet. Similarly, mixing of the warmer air with the cooler air can be made even more difficult where the ambient air inlet is a relatively small space or in close proximity to the components being cooled. To obtain adequate mixing, ducting and mixing plenums may also be needed, which requires extra space. This can mean that there needs to be close coordination between information technology and data center personnel. For instance, this type of air mixing can be especially difficult where it is attempted on an individual machine basis, such as where the preheating is attempted for an individual server, or for a small set of servers. It can also be difficult, however, even when it is attempted on a larger scale, such as to preheat air used for cooling a full rack of servers.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.